Pro-Assad troops, including fighters from the Lebanese militia Hezbollah, launched an offensive against the rebel-held town of Qusair a week ago. They have gained ground, but rebels continue to hold some positions.
Local activist Hadi Abdullah and the Britain-based Syrian Observatory for Human Rights say the artillery barrage began early today. The regime wants to recapture Qusair to open a land corridor between its strongholds in the capital Damascus and on the Mediterranean coast.